"all the color Full Frame CCDs with 9 micron pixel size are now discontinued... so the 22MP backs are going away"
It is/was a very good chip with beautifull big pixels (for beauty, portrait & fashion works)...
[a href=\"index.php?act=findpost&pid=206447\"][{POST_SNAPBACK}][/a]
Don't panic.
For one thing, Dalsa still offers its 22MP sensor, used by some of those backs.
More importantly, the is no evidence or valid theory that using somewhat more somewhat smaller pixels on the same sensor size has any significant disadvantage in visible noise levels or DR, once one allows for options like downsampling or other NR processing from higher pixel count raw files. Especially when technological progress has improved the per pixel read noise levels in the newer higher res. sensors, as is the case with recent Kodak sensors: 22e- RMS in the 22MP, 16e- in the 39MP, 12.5e- in the 50MP.
Have you (or anyone here) compared the results given by downsampling output of 39MP backs to 22MP to what you get from a 22MP back? My prediction is that the downsampled output will probably have better DR and less noise, and will certainly have more resolution.
More DR and less noise because the improved technology of the 39MP sensor gives its pixels about the same DR as the 22MP sensor (through lower read noise and deeper wells), and then the downsampling improves the S/N ratio by averaging noise levels down to a lower level, and thus improves DR.
More resolution roughly because the downsampled output contains 22 million full RGB pixels with 22 million each of red, green and blue values, more than what the 39MP file has to start with (about 20 million green, 10 million each of red and blue) and so is capable of retaining more resolution from the original 39MP file than what what the 22MP sensor gives (11 million green values, 5.5 million each of red and blue.)
In practice, in every comparison I have seen of output from a lower pixel count sensor to output from a higher pixel count sensor downsampled to that lower pixel count, the downsampled image has more resolution.
In fact, you might get about equal resolution by downsampling from 39MP all the way to 11MP, which still retains as many green pixel values and twice and many red and blue pixel values as the 22MP sensor gives.
Has any compared the resolution in conversions from Bayer CFA raw files to RGB formats (like TIFF) at various pixel counts? I would like to see ow close my guess is, that once the RGB output has half as many pixels as the raw, there is little or not gain with higher output pixel counts. Though higher pixel count output can have other virtues, like avoiding jaggies.